Toyota Tacoma (2015-2018) Service Manual: Transfer Shift Motor Control Circuit Circuit Open (P17A8)

Toyota Tacoma (2015-2018) Service Manual / Vf2cm Transfer / Touch Select 2-4 And High-low System / Transfer Shift Motor Control Circuit Circuit Open (P17A8)

DESCRIPTION

This DTC is output when an open circuit in the transfer shift motor drive circuit is detected.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
P17A8	Transfer Shift Motor Control Circuit Circuit Open	Diagnosis Condition: While switching between 2WD and H4 or while switching between H4 and L4 (transfer shift motor operating) with the ignition switch turned to ON Malfunction Status: Open circuit in the transfer shift motor drive circuit Malfunction Time: 0.03 seconds or more Other: 1 trip detection logic	Wire harness and connector 4 wheel drive control ECU Transfer shift actuator assembly

WIRING DIAGRAM

Refer to DTC P17A9 (See page PROCEDURE ).

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - TRANSFER SHIFT ACTUATOR ASSEMBLY)

(a) Disconnect the F12 4 wheel drive control ECU connector.

(b) Disconnect the T4 transfer shift actuator assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F12-8 (TM1) - T4-2 (TM1)	Always	Below 1 Ω
F12-7 (TM2) - T4-1 (TM2)	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	INSPECT TRANSFER SHIFT ACTUATOR ASSEMBLY (TRANSFER SHIFT MOTOR)

(a) Disconnect the T4 transfer shift actuator assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
2 (TM1) - 1 (TM2)	Always	1.5 to 10 Ω

Text in Illustration

*a	Component without harness connected (Transfer Shift Actuator Assembly)

REPLACE 4 WHEEL DRIVE CONTROL ECU

REPLACE TRANSFER SHIFT ACTUATOR ASSEMBLY

Automatic Disconnecting Differential Motor Limit Switch Circuit (P17A4)

DESCRIPTION When the A.D.D. actuator switches between 2WD and 4WD, the DL1 and DL2 terminals of the limit switch and ADD terminal of the A.D.D. position switch change to one of the following ON/O ...

Four Wheel Drive (4WD) Range Signal Circuit Range / Performance (P279E)

DESCRIPTION When the transfer position switch is switched, the 2-4 terminal and LO terminal change to one of the following ON/OFF combinations listed in the table below. Terminal ...

Other materials:

Input/Turbine Speed Sensor "A" Circuit Short to Battery (P071512,P071514,P071531)
DESCRIPTION This sensor detects the rotation speed of the turbine which shows the input turbine speed of the transmission. By comparing the input turbine speed signal (NT) with the output shaft speed sensor signal (SP2), the ECM detects the shift timing of the gears and appropriately controls ...

Dtc Check / Clear
DTC CHECK / CLEAR NOTICE: When the diagnosis system is changed from normal mode to check mode or vice versa, all DTCs and freeze frame data recorded in normal mode are cleared. Before changing modes, always check and make a note of DTCs and freeze frame data. HINT: DTCs which are sto ...

Multi-terrain Select Indicator Light does not Come ON
DESCRIPTION When the transfer gear position is L4, the multi-terrain select indicator light illuminates and control begins. Under any of the following conditions, the multi-terrain select system does not begin control and the multi-terrain select indicator light does not illuminate. Th ...